It sounds like a scene from a daring sci-fi movie where a superhero controls lightning from the highest mountain in the area. However, this is not a scene projected on cinema screens, the superheroes are Swiss scientists in the real world. Last year, experts managed to use powerful laser pulses to control lightning in the sky.

Lasers will protect the airport

The traditional lightning rods that protect buildings from lightning strikes today date back to Benjamin Franklin in the 18th century. However, scientists are trying to find more modern ways to protect buildings from devastating blows from the sky.

“If you have a traditional lightning rod 10 meters high, it will protect an area with a radius of about 10 meters, which is enough for your house, but obviously not enough for an airport, for example, which can be several kilometers long,” the Smithsonian portal quoted the co-author of the study and a physicist at University of Geneva Jean-Pierre Wolf.

According to him, the laser works like a kind of longer virtual rod, which can also be placed in the desired direction and turned on or off at any time.

Up to a thousand pulses per second

How would such a technology work in a real environment on storm clouds, Swiss scientists tested last year. Physicist from École Polytechnique in Palaiseau Aurélien Houard and his colleagues described in the journal Nature Photonics an operation in which they took a powerful laser to the top of Mount Säntis in northeastern Switzerland. They placed it next to a telecommunications tower that gets struck by lightning about a hundred times a year. The telescope then focused the laser beam on a spot approximately 150 meters in the air, just above the top of the 124 meter tower.

The Guardian reports that during storms between July and September, they then fired rapid laser pulses into the clouds for more than six hours. The instruments eventually showed that the laser deflected the direction of the four lightning discharges upwards. According to the scientists, the success of the event was mainly made possible by the speed of the pulses, which the lasers fired about 1,000 times per second. It’s also the first time such research has been conducted in the middle of a real storm.

In addition, the scientists were lucky, because one lightning strike occurred under sufficiently clear conditions, so the researchers could film its path from two directions several kilometers apart. They found that the lightning followed the path of the laser for about fifty meters, confirming their hypothesis that the pulses helped steer the strike. A laser does this by creating an easier path for the electrical discharge to flow. The heated air molecules leave behind a low-density air channel that forms an easier and preferred path for lightning due to electrical conductivity.

The performed operation could bring modern lightning protection to airports, launch pads or even tall buildings. “Metal rods are used almost everywhere for lightning protection, but the area they can protect is limited to a few meters or tens of meters,” Houard said, adding that he hopes they can extend that protection area to at least a few hundred meters if they have enough energy in the laser.

Possible risk to pilots

However, there is one problem. The laser is powerful enough to potentially pose a risk to flying pilots. However, scientists argue that the technique could still be useful, as launch pads and airports often have designated no-fly zones. This safety aspect will have to be thought of when the technology is put into practice.

The physicist finally added that more powerful lasers could control lightning even before it became a real threat. “You avoid it going somewhere else where you can’t control it,” Houard explained.

Professor and director of the Morgan-Botti Lightning Laboratory at Cardiff University, Manu Haddad, then said that although the cost of a laser system is very high compared to the cost of a simple rod, lasers can be a reliable way to direct a lightning discharge.

Another physicist from the University of New Hampshire, Joseph Dwyer, then told the American newspaper The Washington Post that we are still far from the technology that would protect every person from lightning. So for most people, the best option remains a simple and traditional way to avoid being struck by lightning – if they hear thunder, they are supposed to go and hide inside.

Lightning is a huge electrical discharge produced during a thunderstorm. Their charge reaches a temperature of 30,000 degrees Celsius, which is about five times higher than the temperature on the surface of the Sun. The electricity rapidly heats the surrounding air, resulting in the characteristic sound of thunder due to expansion. Also, more than a billion lightning strikes the Earth each year, causing thousands of deaths and billions of dollars in damage. The strikes also pose a danger to electronics, including sensitive equipment housed in aircraft and space rockets.